College of Liberal Arts and Sciences, School of Life Sciences, University of Westminster, 115 New Cavendish Street, London, W1W 6UW, UK.
William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK.
Eur J Pharmacol. 2020 Apr 5;872:172971. doi: 10.1016/j.ejphar.2020.172971. Epub 2020 Jan 28.
Human melanocortin MC1 and MC3 receptors expressed on C-20/A4 chondrocytes exhibit chondroprotective and anti-inflammatory effects when activated by melanocortin peptides. Nearly 9 million people in the UK suffer from osteoarthritis, and bacterial infections play a role in its development. Here, we evaluate the effect of a panel of melanocortin peptides with different selectivity for human melanocortin MC1 (α-MSH, BMS-470539 dihydrochloride) and MC3 ([DTrp]-γ-MSH, PG-990) receptors and C-terminal peptide α-MSH(KPV), on inhibiting LPS-induced chondrocyte death, pro-inflammatory mediators and induction of anti-inflammatory proteins. C-20/A4 chondrocytes were treated with a panel of melanocortin peptides prophylactically and therapeutically in presence of LPS (0.1 μg/ml). The chondroprotective properties of these peptides determined by cell viability assay, RT-PCR, ELISA for detection of changes in inflammatory markers (IL-6, IL-8 and MMP-1, -3 and -13) and western blotting for expression of the anti-inflammatory protein heme-oxygenase-1. C-20/A4 expressed human melanocortin MC1 and MC3 receptors and melanocortin peptides elevated cAMP. LPS stimulation caused a reduction in C-20/A4 viability, attenuated by the human melanocortin MC1 receptor agonist BMS-470539 dihydrochloride, and MC3 receptor agonists PG-990 and [DTrp]-γ-MSH. Prophylactic and therapeutic regimes of [DTrp]-γ-MSH significantly inhibited LPS-induced modulation of cartilage-damaging IL-6, IL-8, MMPs -1,-3 and -13 mediators both prophylactically and therapeutically, whilst human melanocortin MC1 and MC3 receptor agonists promoted an increase in HO-1 production. In the presence of LPS, activation of human melanocortin MC1 and MC3 receptors provided potent chondroprotection, upregulation of anti-inflammatory proteins and downregulation of inflammatory and proteolytic mediators involved in cartilage degradation, suggesting a new avenue for osteoarthritis treatment.
人类黑素皮质素 MC1 和 MC3 受体在 C-20/A4 软骨细胞上表达，当被黑素皮质素肽激活时，表现出软骨保护和抗炎作用。英国有近 900 万人患有骨关节炎，细菌感染在其发病中起作用。在这里，我们评估了一组具有不同选择性的黑素皮质素肽对人类黑素皮质素 MC1（α-MSH、BMS-470539 二盐酸盐）和 MC3（[DTrp]-γ-MSH、PG-990）受体和 C 末端肽α-MSH（KPV）的影响，以抑制 LPS 诱导的软骨细胞死亡、促炎介质和诱导抗炎蛋白。C-20/A4 软骨细胞在 LPS（0.1μg/ml）存在的情况下用一组黑素皮质素肽进行预防性和治疗性治疗。通过细胞活力测定、RT-PCR、ELISA 检测炎症标志物（IL-6、IL-8 和 MMP-1、-3 和-13）的变化以及 Western blot 检测抗炎蛋白血红素加氧酶-1 的表达来确定这些肽的软骨保护特性。C-20/A4 表达人类黑素皮质素 MC1 和 MC3 受体，黑素皮质素肽升高 cAMP。LPS 刺激导致 C-20/A4 活力降低，这种降低被人类黑素皮质素 MC1 受体激动剂 BMS-470539 二盐酸盐和 MC3 受体激动剂 PG-990 和[DTrp]-γ-MSH 减弱。[DTrp]-γ-MSH 的预防性和治疗性方案显著抑制了 LPS 诱导的软骨损伤性 IL-6、IL-8、MMPs-1、-3 和-13 介质的调节，同时人类黑素皮质素 MC1 和 MC3 受体激动剂促进了 HO-1 产生的增加。在 LPS 存在的情况下，人类黑素皮质素 MC1 和 MC3 受体的激活提供了强大的软骨保护作用，上调抗炎蛋白，下调参与软骨降解的炎症和蛋白水解介质，这为骨关节炎治疗提供了新途径。
